Add ancestryProof graphql endpoint

[georgeee]

PR implements a new grapql endpoint ancestryProof that retrieves state body hash sequences along with intial state hash that results into target state hash.

Type of the new graphql query:

ancestryProof(stateHash: StateHash | null, depth: Int | null) : Pair<StateHash, StateBodyHash[]>

If stateHash isn't provided, best tip is used. If depth is not provided, 290 will be used as a value.

Explain how you tested your changes:

• A new test suite for the graphql's implementation feature is added

Checklist:

• Dependency versions are unchanged
  • Notify Velocity team if dependencies must change in CI
• Modified the current draft of release notes with details on what is completed or incomplete within this project
• Document code purpose, how to use it
  • Mention expected invariants, implicit constraints
• Tests were added for the new behavior
  • Document test purpose, significance of failures
  • Test names should reflect their purpose
• All tests pass (CI will check this if you didn't)
• Serialized types are in stable-versioned modules
• Does this close issues? List them

• Closes Feature Request: Expose AncestryProof to grapqhQL schema #18356

[georgeee]

!ci-build-me

[martyall]

nice work 🎉

[georgeee]

!ci-build-me